I know there has been much talk about the mid and O/S versions of the POG on the forum but there isn't one definitive post which clears everything up.
I was wondering if people knowledgeable on the subject could post each version of the mid and O/S with pictures of side/top/cover (if possible) or description of each detail so whenever we need to refer to it for purchases, clarification or authentication we can do it.

I will give a beginning run down and please let me know if I'm on the right track.

First the OS

POG 1 = Tear dropped shaped head single line with no grommets/no bumper and no printing on top or side or racket (possibly just sticker) except for Prince/graphite- circa 1978

POG 2 = Tear dropped shaped head, single line with grommets/no bumper no printing on top or side or racket (possibly just sticker) except for Prince/graphite- circa 1980?

POG 3 = Normal shaped head, single line with grommets and bumper, printing on side is "graphite series 110" top has no printing front is Prince/Graphite. Printed stringing weight is 70-80 - Circa 1983

From what I've heard on the forum the two 4 stripe versions are identical except for their printing; I assume this is also true for POG 3 and 3.5. Can someone please tell me if this is true?

On what version does the POG mid start, POG 3? And what are the versions/half-versions of the mid?

It will be great to get a neat and organized resource for all the POG lovers out there. I've searched around and there is no place that gives a complete (or even partial) detailed description/history with pictures of the POG mid and OS.